The following processes for producing 4-acyloxy-2-methyl-2-buten-1-al, particularly4-acetoxy-2-methyl-2-buten-1-al have been known. ##STR1##
This process is uneconomical because it uses expensive reagents such as p-toluenesulfonic acid. Further, the yield is at most 60% because the unstable halohydrin compound is produced under strongly acidic conditions and subjected to heating for hours. This process is environmentally unsuitable because of dimethyl sulfide responsible for the bad smell produced in the reaction. ##STR2##
This process uses a heavy metal such as manganese and requires the removal of the metal from the resulting desired compound 4-acyloxy-2-methyl-2-buten-1-al. ##STR3##
Each of the above known processes for producing 4-acyloxy-2-methyl-2-buten-1-al is problematic and disadvantageous for an industrial process. For example, the processes require many reaction steps to obtain the desired compound from readily available industrial starting compounds, require severe reaction conditions, need reagents that must be handled with great care, involve unstable intermediate compounds, need expensive reagents, involve a low yield step, etc.